Ferrous fumarate/iron polysaccharide Side Effects

Medically reviewed by Drugs.com. Last updated on Jul 23, 2023.

Applies to ferrous fumarate/iron polysaccharide: oral capsule.

Serious side effects

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Black, tarry, or bloody stools.
• Fever.
• Very upset stomach or throwing up.
• Very bad belly pain.
• Throwing up blood or throw up that looks like coffee grounds.

Other side effects

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Upset stomach or throwing up.
• Not hungry.
• Constipation.
• Change in color of stool to green.
• Diarrhea.
• Belly pain.
• Stomach cramps.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

For Healthcare Professionals

Applies to ferrous fumarate/iron polysaccharide: oral capsule.

Gastrointestinal

Cases of gastrointestinal discomfort are typically mild and subside with continuation of therapy. According to the manufacturer, ferrous fumarate-iron polysaccharide is best absorbed when administered at bedtime; however, gastrointestinal side effects may be minimized when administered with a meal.

Constipation may be relieved by administering docusate sodium 100 mg to 200 mg per day in addition to increasing the intake of oral fluids, such as water.^[Ref]

Gastrointestinal side effects have included nausea, constipation, anorexia, heartburn, vomiting and diarrhea. In addition, stools may appear darker in color in patients taking ferrous fumarate.^[Ref]

Immunologic

It has been hypothesized that gastroenteritis is caused by bacteria that become virulent in the presence of iron overload resulting in a systemic infection. Treatment consists of discontinuing deferoxamine and initiating appropriate antimicrobial therapy.^[Ref]

Immunologic side effects associated with oral iron products have rarely included gastroenteritis associated with Yersinia enterocolitica and Listeria monocytogenes in patients with iron overload status receiving treatment with deferoxamine.^[Ref]

Other

Iron overload (i.e., hemosiderosis) has been reported in patients genetically predisposed, or have underlying disorders, that augment the absorption of iron. It has also occurred following administration of excessive parenteral iron therapy, combination of oral and parenteral iron, or in patients with hemoglobinopathies that were erroneously diagnosed as iron deficiency anemia. Hemosiderosis is treated with repeated phlebotomy or long-term administration of deferoxamine. The liver is particularly susceptible to toxicity in iron-overload states.^[Ref]

Other side effects have included iron overload (hemosiderosis). Secondary hemochromatosis due to prolonged iron ingestion has been reported rarely.^[Ref]

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

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